Question: Express this product in scientific notation: $(7.80\times 10^{1})\times (4.00\times 10^{0})$
Solution: Start by collecting like terms together. $= (7.80\times 4.00) \times (10^{1}\times 10^{0})$ When multiplying exponents with the same base, add the powers together. $= 31.2 \times 10^{1\,+\,0}$ $= 31.2 \times 10^{1}$ To write the answer correctly in scientific notation, the first number needs to be between $1$ and $10$ . In this case, we need to move the decimal one position to the left without changing the value of our answer. $ $ We can use the fact that $31.2$ is the same as $3.120 \times 10$ $ = {3.120 \times 10} \times 10^{1} $ $= 3.120\times 10^{2}$